Nuclear radiation detected optical pumping of neutron deficient Hg isotopes

The extension of the Nuclear Radiation Detected Optical Pumping method to mass-separated samples of isotopes far off stability is presented for a series of light Hg isotopes produced at the ISOLDE facility at CERN. The isotope under investigation is transferred by an automatic transfer system into the optical pumping apparatus. Zeeman scanning of an isotopically pure Hg spectral lamp is used to reach energetic coincidence with the hyperfine structure components of the 6s21S0-6s6p3P1 (lambda = 2537 A) resonance line of the investigated isotope and the Hg lamp. The orientation build up by optical pumping is monitored via the asymmetry or anisotropy of the nuclear radiation. Nuclear spins, magnetic moments, electric quadrupole moments and isotopic shift are obtained for 181Hg-191Hg using the β-asymmetry as detector. The extension of the method using the γ-anisotropy is discussed and measurements on 193Hg are presented. (orig./HK)